About: http://webisa.webdatacommons.org/114140144

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	So, yes, stress is a headache trigger, but it is not the cause of the headache. (You can read about the distinction in the fourth paragraph of this post.) Thanks to Dr. Peterson for pointing out my mistake.
http://www.w3.org/ns/prov#wasQuotedFrom	thedailyheadache.com